The center of Harvey has now moved into the Gulf of Mexico. A majority of impacts from Harvey are in the rain bands located to the northeast of the center. Winds have become gustier in Southeast Texas and the Coastal Plains this afternoon, but we are not expecting Harvey to regain hurricane intensity while it is in the Gulf. What Harvey will do while in the Gulf is push more moisture into Southeast Texas over the next 36 hours. This increased moisture means we’ll see additional rainfall – some of which will be heavy. Even light rain could cause additional flooding issues in Southeast Texas.
Harvey is crawling toward the southeast and won’t move much through Tuesday afternoon. A gradual turn toward the northeast is expected Tuesday Night and early Wednesday. The center of Harvey will make landfall very near Galveston Wednesday morning. From there it’ll finally start moving more quickly to the northeast in Far Southeast Texas and should exit Texas by Wednesday night. That forecast is still subject to considerable change as there really is no ‘steering’ mechanism in the upper-levels. That is why Harvey has been sticking around for days. While only a little intensification is expected in the wind department, we will have to watch for an increased risk of storm surge across the far Southeast Texas coast through Wednesday. I don’t expect anything like the surge from a few days ago, but coastal flooding issues may begin to resume. Those concerns are secondary compared to the flooding issues and additional rainfall expected through the mid-week.
We still have at least two days more of rain expected in Southeast Texas. In addition, as Harvey starts to move north/northeast we’ll see rain chances shift northward into East Texas as well. The latest forecast from the Weather Prediction Center indications the potential for an additional 15 to 20 inches of rain in Southeast Texas – including Harris, Fort Bend, Brazoria, and surrounding counties. It will not rain at all times nor are we anticipating 15 inches in 3 hours like the other night in South Houston. We’ve had rainfall rates between 1 and 2 inches this afternoon in Harris County. That rain will continue into this evening. Like the last few nights, an additional band of very heavy rainfall is expected to develop and ‘train’ over parts of Southeast Texas for several hours tonight. We can’t determine exactly where that band will set up until it’s actually forming, but there will likely be 2 to 4 inches of rain under that band per hour – and some locations will likely see 5-10 inches of rain in a 5-8 hour period tonight. That will cause new flooding to develop or exacerbate already ongoing flooding. River flooding has become a major threat across eastern sections of Central Texas and in Southeast Texas. These river-flood issues will be the longer duration event and continue into September.
Tropical Storm Harvey Advisory Number 34
NWS National Hurricane Center Miami FL AL092017
400 PM CDT Mon Aug 28 2017
…SURFACE OBSERVATIONS SHOW THAT HARVEY HAS 45 MPH WINDS…
…LIFE-THREATENING FLOODING CONTINUES OVER SOUTHEASTERN TEXAS…
…DO NOT ATTEMPT TO TRAVEL IN THE AFFECTED AREAS IF YOU ARE IN
A SAFE PLACE AND DO NOT DRIVE INTO FLOODED ROADWAYS…
SUMMARY OF 400 PM CDT…2100 UTC…INFORMATION
ABOUT 45 MI…70 KM E OF PORT OCONNOR TEXAS
ABOUT 145 MI…235 KM SW OF PORT ARTHUR TEXAS
MAXIMUM SUSTAINED WINDS…45 MPH…75 KM/H
PRESENT MOVEMENT…ESE OR 110 DEGREES AT 3 MPH…6 KM/H
MINIMUM CENTRAL PRESSURE…997 MB…29.44 INCHES
WATCHES AND WARNINGS
CHANGES WITH THIS ADVISORY:
The Tropical Storm Warning has been extended east of Cameron,
Louisiana, to Intracoastal City, Louisiana.
A Storm Surge Watch has been issued from Port Bolivar, Texas, to
Morgan City, Louisiana.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Tropical Storm Warning is in effect for…
* Mesquite Bay to Intracoastal City
A Storm Surge Watch is in effect for…
* Port Bolivar to Morgan City
Catastrophic and life-threatening flooding continues in southeastern
Texas. Please see warnings and other products issued by your
local National Weather Service office for additional information on
this life-threatening situation.